[Issue 988] DMD allows invalid LOCK prefix in inline assembler

[Sean Kelly]

d-bugmail at puremagic.com wrote:
>
> The LOCK prefix can be prepended only to the following instructions and only to
> those forms
> of the instructions where the destination operand is a memory operand: ADD,
> ADC, AND,
> BTC, BTR, BTS, CMPXCHG, CMPXCH8B, DEC, INC, NEG, NOT, OR, SBB, SUB, XOR,
> XADD, and XCHG.

Darnit, I dunno why I thought this was supposed to work.  It's not like 
I haven't read this clause enough :-p  I'll use CAS instead.  Thanks!